Resumo

MEHTA, Jignasu P; PANDYA, Kahan I  e  GODHANI, Dinesh R. Electrochemical Investigation of Divalent State of Praseodymium and Samarium in Non-aqueous Medium. Port. Electrochim. Acta [online]. 2015, vol.33, n.3, pp.183-194. ISSN 0872-1904.  https://doi.org/10.4152/pea.201503183.

The aim of present study is to establish the not known divalent state of praseodymium and samarium in non-aqueous medium at 298.15 K and atmospheric pressure. Potentiostatic and galvanostatic methods were used to characterize the divalent states of both lanthanides. Under the specified experimental conditions, samarium and praseodymium showed two reduction steps at glassy carbon electrode in non-aqueous medium. Cathodic and corresponding anodic peak potential and peak currents were calculated for samarium and praseodymium ions at different scan rates. The results also suggest that the scan rate has great influence on the behaviour of both lanthanides. Diffusion coefficient (D × cm² s^-1) and heterogeneous forward rate constant (k^o_fh × cm s^-1) have been evaluated. Transition time (τ) has also been evaluated for Pr(III)/Pr(II), Pr(II)/Pr(0) coupled systems, suggesting that the system is approaching from irreversible with increasing the scan rates. The effects of changing the scan rate and donor number on the electrochemical behavior of both lanthanides have been examined at 298.15 K and atmospheric pressure.

Palavras-chave : Praseodymium; samarium; -aqueous medium; potentiostatic method; galvanostatic method; Sand equation.

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